Merge branch 'dev' of https://github.com/facebook/zstd into ldm-mergeDev

lib/compress/zstd_double_fast.h

@@ -5,6 +5,7 @@
  * This source code is licensed under both the BSD-style license (found in the
  * LICENSE file in the root directory of this source tree) and the GPLv2 (found
  * in the COPYING file in the root directory of this source tree).
+ * You may select, at your option, one of the above-listed licenses.
  */
 
 #ifndef ZSTD_DOUBLE_FAST_H